Reversing tool



Patented Mar. 15, 1938 UNITED STATES PATENT OFFICE Claims.

The invention relates to a reversing tool of the type which is used in unscrewing pieces of pipe which have been lodged in a well bore.

In the drilling of wells by the rotary method, a

5 string of pipe is used to rotate the drill bit and the usual practice is to couple the drill pipe sections together with right-hand threads. In some instances this pipe becomes broken, unscrewed, or otherwise separates, and a job of fishing out the portions left in the well occurs. In other instances the string of pipe may become stuck in the well by virtue of caving formations or for many and various other reasons, and it is desirable to unscrew such sections as can be reached and remove them from the well. 7

In other instances the casing, tubing, or other string of pipe in the well is to be unscrewed and removed.

Various types of tools have been devised for unscrewing the pipe sections. In some instances a string of left-hand threaded pipe is provided and, of course, in this way the right-hand threaded sections can be unscrewed by suitably attaching the left-hand string to the right-hand 25 string. Strings of left-hand pipe are a rarity in the oil fields, however, and the present tool has been devised with a view of utilizing a string of right-hand threaded pipe which is available by providing the present mechanism for attachment to the lower end thereof so that the right-hand rotation of the string of operating pipe canbe reversed and when the lower end of the present tool is thus connected to a string of pipe it will be caused to rotate in a left-hand direction so that 35 it will be unscrewed. g

It is one of the objects of the invention to provide a reversing tool which will operate by anchoring a portion thereof in the well bore so that it will absorb the reaction caused in reversing the direction of rotation.

sun another object .of the invention is to pro-- vide a reversing tool through which circulation may be maintained while the reversing operation 55 is in progress, I

Still another object of the invention is to provide a fluid pressure operated anchor member for a reversing tool.

Other and further objects of the invention will Another object of the invention is to provide a be readily apparent when the following description is consideredin connection with the accompanying drawing wherein:

Fig. 1 is a central, vertical, sectional view illustrating the tool in assembled positionready to be lowered into the well bore.

Figs. 2, 3, and 4 are sections taken on the lines 22, 3-3, and 4-4 respectively, of Fig. 1 and looking in the direction of the arrows.

The operating string is indicated generally at 2 and may be a string of drill pipe or tubing which is of suflicient strength to impart rotation to the head 3 of the reversing tool. This head 3 has fixed to its lower end the driving spindle i which is held in lockedposition with the head 3 by means of the locking keys 5. This driving spindle carries a driving head .6 which is fixed to the lower end I of the driving spindle 4 and carries a set of geared teeth I on its lower face. These teeth are in turn arranged to mesh with the driving pinions 8 and 8 which are carried by the stub shafts Ill. The reversing head ii is mounted below the driving pinion 8 and is provided withteeth i2 similar to the teeth 1 and this head carries the reversing connection it which is threaded at Hi for connection to any suitable grappling tool so that the pipe to be reversed can be connected to this reversing tool or the threads M may be screwed directly into the pipe which is to be reversed.

It seems obvious that when the pipe 3 rotates in one direction that the pipe l3 will rotate in the opposite direction, because of the reversal of chored against rotation so that the stress transfer can be absorbed thereby and to accomplish this the coupling 2@ which carries the stud shafts 10 forms part of an anchor assembly indicated generally at El. This assembly includes a lower cap 22 which is connected to the coupling 20 and serves as a bearing for the reversing head H because of the beveled face 23 thereon. This cap 22 also serves as a bearing for the reversing nipple' I 3 which is carried by the reversing head i 8.

Above the couplingifi is packer support member 25 which serves as a support for the expansible member 25. This member is arranged for expanding movement by the spring members 21, a plurality of which are arranged inside of the'expansible' member 26. These fingers are anchored at their lower end 28 in the supporting member 25 and project upwardly inside of the packer member where they are received with v in a bracket 30 which is carried by the piston 3|.

The upper end of the packer 28 is anchored to.

. the support member 32 and this support -member in turn carries the barrel 33 which serves as a cylinder for the piston 30.-

; When thedevice is to-be anchored in the well 'bore fluid'p'ressure is applied to the operating string 2 so that it will pass through the openings 33 in the head 3 and be applied against the upper face of the piston 3|. This moves the piston 3| downwardly to extend the spring members 21 and expands the packer member 26 against the wall of the well bore. The device is now anchored and so long as fluid pressure is applied in the pipe 2 the device will remain anchored in the well bore. If the operating string is now rotated the anchor member 2| will be held stationary by the packer 26 and any longitudinal stresses between the anchor assembly and the operating string 2 will be absorbed by the antifriction bearings 35 positioned between the head 3 and the cap member 35 of the anchor assembly 2 I. The rotation of the operating string is imparted to the head 3, spindle 4 and driving head 6, which in turn rotates the pinions 8 and 8' to cause rotation of the driven head II and connection |3 reversely to that of the operating string. A conduit 9 serves to allow a circulation of fluid through the tool.

In some instances it is desirable to rotate the entire assembly as a unit and avoid using it as areversing mechanism. In other words, the pipe nipple 3 or reversing connection must rotate in the same direction as the head 3 and the operating string 2. To accomplish this, the anchor assembly 2| must also rotate with the head 3. With this in mind the upstanding bars 40 have been fixed to the upper end of the piston 3| and as seen in Fig. 2 are arranged for sliding movement between the flanges 4| which are carried by the inside of the barrel 33. The bars 40 also project upwardly into the recess 42 which is formed in the periphery of the head 3. When the parts are as seen in Fig. 1 with insuflicient fluid pressure applied to the piston to cause expansion of the springs 21, then the locking bars 40 will rest in the recess 42 and be lodged between the ribs 4| so that all of the parts are locked together as a unitary structure. When fluid pressure is applied and the piston moves downwardly so that the upper end of the bar 40 moves out of the recess 42, then the head 3 is released for relative rotation with respect to the anchor assembly 2|. When fluid pressure is relieved, however, the spring members 21 will tend to raise the piston 3| and by a slight amount of rotation the recess 42 and the bars 40 can again be aligned and the device locked in position. This is sometimes desirable in order to disconnect the tool and for other purposes during' the operation thereof.

Broadly the invention contemplates a reversing tool which can be anchored in the well bore by fluid pressure and used either as a reversing tool or as a unitary assembly, one advantage residing in the fact that the tool can be anchored and released by merely applying and releasing fluid pressure.

What is claimed is:

1. A reversing tool for unscrewing pipe in wells comprising a drive string, a driven connection, an anchor member, and means on said anchor interengaging with said string and said connection whereby said connection rotates in a reverse direction from that of said string, said anchor member including an expansible packer.

2. A reversing tool for unscrewing pipe in wells comprising a drive string, a driven connection, an anchor member including a packer, means on said anchor interengaging with said string and said connection whereby said connection rotates aurora ina reverse direction from that of said string, and fluid operated means to set said anchor.

3. A fluid pressure anchor for reversing tools comprising a packer member of expansible material, spring means within said packer member, a piston engaging said means and adapted to move longitudinally of said packer to move said.

said assembly against rotation, a driving head swiveled to said assembly, a drive spindle carried by said head, a set of reversing gearing including a reversing head also swiveled in said anchor, whereby the direction of rotation of said last head is reversed relative to said first head.

5. A reversing tool comprising a drive head, a drive spindle carried thereby, an anchor assembly swiveled on said head, a drive gearon said spindle, idler gears on said anchor, means movable on said anchor to set the same against rotation, a driven head geared to said idler gears whereby said driven head rotates reversely of said drive head when said anchor is set, and fluid pressure actuated means to'set and release said anchor assembly and to locksaid headsagainst relative rotation when the anchor is released. I

6. A reversing tool comprising a drive head, a drive spindle carried thereby, an anchor assembly swiveled on said head, a drive gear on said spindle, idler gears on said anchor, means movable on said anchor to set the same against rotation, a driven head geared to said idler gears whereby said driven head rotates reversely of said drive head when said anchor is set, fluid pressure actuated means to set and release said anchor assembly, and releasable means cooperating with said first mentioned means for looking said heads and anchor to operate as a unit-when said anchor assembly is released.

7. A reversing tool including drive and driven members, a reversing mechanism and means to anchor said mechanism against relative rotation comprising a fluid pressure actuated pischor, and locking means for said tool to be released by the pressure of fluid from said stream.

9. A reversing tool including drive and driven members, a reversing mechanism and means to lock said mechanism against relative rotation of said members, said means comprising a. fluid pressure actuated piston, and an anchor for the tool which is also actuated by fluid pressure.

10. A reversing tool comprising a. drive head, a driven head, a reversing mechanism between said heads, an anchor assembly swiveled on said drive head, said assembly including a cylinder having a piston therein, means on said piston for locking the drive head and the anchor assembly against relative rotation when .-the piston is in retracted position and for releasing the drive head and anchor assembly for relative rotation when the piston is advanced and the too is anchored in position in a well.

VERNON C. POSEY. 

